Over the last 100 years of the industrial revolution, human civilization has been performing a remarkable experiment on Earth’s climate system. Because of a variety of activities related to population growth and economic development, most notably the burning of fossil fuels, humans have increased the concentration of carbon dioxide in the atmosphere by approximately 30%. Carbon dioxide is a gre...

Neutral atomic sodium and chlorine emissions from cleaved, single-crystal NaCl 100 surfaces due to pulsed, 248-nm excimer laser irradiation have been characterized by time-resolved, quadrupole mass spectroscopy. At laser fluences below the threshold for optical breakdown, the resulting time-of-flight signals are consistent with particles emitted in thermal equilibrium with a laser-heated surfac...

vacuum drying of salicornia herbacea l. was performed at different drying temperatures (50, 60, 70, and 80c) to evaluate the drying characteristics and the effect of drying temperatures on the quality of salicornia. as the drying temperature increased, the drying time decreased significantly (p< 0.05). the drying rate decreased with decrease in moisture content and increase in drying time. on ...

CO2 reforming of methane (CRM) over unpromoted and potassium promoted Ni/Al2O3 catalysts was studied. The catalysts were prepared by impregnation method and characterized by X-ray diffraction (XRD), N2 adsorption (BET), temperature programmed reduction (TPR), temperature programmed oxidation (TPO) and scanning electron microscope (SEM) techniques. The obtained results showed that addition of K2...

study of terrain including vegetation, water resources, land types including soil texture and classification are cases that require data with high precision. accurate and high quality data can lead us to a better, more accurate results.in this context, remote sensing data is a great tool for the detection and identification of patterns. sebal (surface energy balance algorithm) is a relatively n...

land surface temperature (lst) is a significant parameter for many applications. many studies have proposedvarious algorithms, such as the split-window method, for retrieving surface temperatures from two spectrallyadjacent thermal infrared bands of satellite data. each algorithm is developed for a limited study area andapplication. in this paper, as part of developing an optimal split-window m...

This paper presents a numerical analysis using the CFD Fluent (6.3.26 version) program to identify the effects that can be generated when using radiant tubes with internal recirculation of combustion products, but with a pre-combustion chamber. The numerical results are validated with an experimental assembly based on the outlet deviation of gases temperature. These deviations were less than 5 ...

The use of titanium and its alloys has increased in various industries recently, because of their superior properties of these alloys. Titanium alloys are generally classified as difficult to machine materials because of their thermo-mechanical properties such as high strength-to-weight ratio and low thermal conductivity. Laser Assisted Machining (LAM) improves the machinability of high strengt...

the significant consumption of gas in the world results in the emission of greenhouse gases into atmosphere. abadan refinery has always been the biggest and oldest oil refinery in the middle east and has a variety of refined products. after six months of collecting data about pollutant concentration emitted from a stack of old furnaces of units 75 and new unit 200, the emission factor of the po...